fix: spotify importer uses same iTunes lookup as global search for artwork + metadata

- _loadSpotifyTrackArtwork: rewritten to call itunesSearch() directly from browser (same as global search) instead of backend endpoint — same quality, works for all regions
- enriches track objects with collectionName, releaseDate, trackNumber, trackExplicitness so downloads get full metadata too
- 8-concurrent batch to avoid hammering iTunes
- adds onerror fallback to makeGlobalTrackItem img so broken URLs show 🎵 placeholder

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components.js

@@ -71,7 +71,7 @@ export function makeGlobalTrackItem(t, idx, list) {
   el.className = 'gtrack-item';
   const art = t.artworkUrl60 || t.artworkUrl100 || '';
   el.innerHTML = `
-    <div class="gtrack-art">${art ? `<img src="${art}" loading="lazy">` : '<div style="width:100%;height:100%;display:flex;align-items:center;justify-content:center;font-size:22px">🎵</div>'}</div>
+    <div class="gtrack-art">${art ? `<img src="${art}" loading="lazy" onerror="this.parentNode.innerHTML='<div style=\\'width:100%;height:100%;display:flex;align-items:center;justify-content:center;font-size:22px\\'>🎵</div>'">` : '<div style="width:100%;height:100%;display:flex;align-items:center;justify-content:center;font-size:22px">🎵</div>'}</div>
     <div class="gtrack-info">
       <div class="gtrack-title">${esc(t.trackName||t.collectionName||'—')}${t.trackExplicitness==='explicit'?'<span class="explicit-badge">E</span>':''}</div>
       <div class="gtrack-sub">${esc(t.artistName||'—')} · ${esc(t.collectionName||'')} ${t.releaseDate?'· '+new Date(t.releaseDate).getFullYear():''}</div>

src/spotify.js

@@ -1,5 +1,6 @@
 import { S } from './state.js';
 import { esc, toast } from './utils.js';
+import { itunesSearch } from './api.js';
 // Circular imports — safe (only used inside function bodies)
 import { makeGlobalTrackItem } from './components.js';
 import { openDlModal } from './ui.js';
@@ -159,43 +160,47 @@ function _renderSpotifyPreview(data) {
 }
 
 async function _loadSpotifyTrackArtwork(tracks, listEl) {
-  try {
   const artEls = listEl.querySelectorAll('.gtrack-art');
 
-    // Render any artwork already present in the Spotify data immediately
+  // Show any Spotify artwork that's already present immediately
   tracks.forEach((t, i) => {
     const url = t.artworkUrl100 || t.artworkUrl60 || '';
     if (!url) return;
     const el = artEls[i];
     if (!el) return;
-      const img = document.createElement('img');
-      img.src = url; img.loading = 'lazy';
-      el.innerHTML = ''; el.appendChild(img);
+    _setArt(el, url);
   });
 
-    const payload = tracks.map((t, i) => ({
-      idx: i,
-      trackName: t.trackName,
-      artistName: t.artistName,
-      existingArt: t.artworkUrl100 || t.artworkUrl60 || '',
+  // Enrich each track with iTunes data — same call as global search
+  const CONC = 8;
+  for (let i = 0; i < tracks.length; i += CONC) {
+    const batch = tracks.slice(i, i + CONC);
+    await Promise.all(batch.map(async (t, bi) => {
+      const idx = i + bi;
+      try {
+        const firstArtist = (t.artistName || '').split(/\s*[,/•]\s*/)[0].trim();
+        const results = await itunesSearch(`${t.trackName} ${firstArtist}`, 'musicTrack', 1);
+        const match = results[0];
+        if (!match) return;
+        // Enrich track object so downloads get correct metadata
+        if (match.artworkUrl100)      t.artworkUrl100      = match.artworkUrl100;
+        if (match.collectionName)     t.collectionName     = match.collectionName;
+        if (match.releaseDate)        t.releaseDate        = match.releaseDate;
+        if (match.trackNumber)        t.trackNumber        = match.trackNumber;
+        if (match.trackExplicitness)  t.trackExplicitness  = match.trackExplicitness;
+        if (window._spotifyResolved?.tracks?.[idx]) Object.assign(window._spotifyResolved.tracks[idx], t);
+        const url = match.artworkUrl100 || match.artworkUrl60 || '';
+        if (url) _setArt(artEls[idx], url);
+      } catch { /* non-critical */ }
     }));
-    const res = await fetch(`${S.cfg.backendUrl}/api/spotify/track-artwork`, {
-      method: 'POST',
-      headers: { 'Content-Type': 'application/json' },
-      body: JSON.stringify({ tracks: payload }),
-    });
-    if (!res.ok) return;
-    const { results } = await res.json();
-    for (const r of results) {
-      if (!r.artworkUrl || r.idx == null) continue;
-      const el = artEls[r.idx];
-      if (!el) continue;
-      const img = document.createElement('img');
-      img.src = r.artworkUrl; img.loading = 'lazy';
-      el.innerHTML = ''; el.appendChild(img);
-      if (window._spotifyResolved?.tracks?.[r.idx]) {
-        window._spotifyResolved.tracks[r.idx].artworkUrl100 = r.artworkUrl;
   }
-    }
-  } catch { /* artwork loading is non-critical */ }
+}
+
+function _setArt(el, url) {
+  if (!el) return;
+  const img = document.createElement('img');
+  img.loading = 'lazy';
+  img.onerror = () => { el.innerHTML = '<div style="width:100%;height:100%;display:flex;align-items:center;justify-content:center;font-size:22px">🎵</div>'; };
+  img.src = url;
+  el.innerHTML = ''; el.appendChild(img);
 }